PS/2 and VGA ports have voltage running over some of the pins to either
power the device (in the case of PS/2), or provide timing and other
functions (in the case of VGA). In either case, you can seriously damage
either the controller in the computer or the device on the other end by
disconnecting or connecting these kinds of devices while the power is on.
The damage is done when voltage surges uncontrolled down those lines by the
act of connecting things, a problem that USB does not suffer from. It's like
the little blue arc you see when you plug in a vacuum cleaner that is
already switched on. A vacuum cleaner can handle the momentary jump in
voltage, but chips are much more sensitive. An arc or short can apply
several hundred times the rated voltage to an IC on either end of the cable
and fry the components inside, or worse, you can pick up an electrostatic
discharge at several thousand times the rated voltage for a circuit. Such an
occurance is not predictable, so it turns into a game of Russian Roullette
where one does not know the count of cylinders in the gun, nor how many
cartridges have been loaded. Best practice is to power down fully before
connecting or disconnecting a device that uses VGA, DVI, PS/2, AT, serial,
or parallel port connections (pretty much anything other than USB or
Firewire).
----- Original Message -----
From: "Tony M." <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, April 21, 2008 8:06 PM
Subject: Re: [PCBUILD] Running Without a Monitor or keyboard - Windows Home
Server
> With all due respect...
> It is NOT safe to plug and unplug older keyboards/mice (ie: ps2). USB
> items do not have this limitation.
>
> Tony mayer
>
>
>
> Mark Rode wrote:
>>> 1. Does anyone know if there is a way to run the computer without a
>>> video card?
>>
>> Sure, first try to disable the video card in the BIOS, there is often a
>> setting for this.
>>
>>> I guess the same question will occur for the keyboard,
>>
>> Just remove the startup check in the BIOS, so it POSTs without checking
>> for anything.
>>
>>> 2. If the monitor is unplugged and the screen saver is on, set to
>>> black, does the video card use much power?
>>
>> no, not an old AGP or PCI card with less then 16 megs of RAM. Your watt
>> meter will let you know exactly how much, but I bet it is insignificant.
>>
>> However, I would install an old video card, and use a USB keyboard and
>> mouse. You can unplug the monitor, mouse and keyboard once you are up
>> and running.... and then plug them back in without a reboot if you need
>> them. If, or should I write when, you have a problem, it will be really
>> nice to have some kind of video, mouse and keyboard support.
>>
>> Mark Rode
>> The Nospin Group
>> PCBUILD maintains hundreds of useful files for download
>> visit our download web page at:
>> http://freepctech.com/downloads.shtml
>>
>>
>
> PCBUILD maintains hundreds of useful files for download
> visit our download web page at:
> http://freepctech.com/downloads.shtml
>
PCBUILD's List Owners:
Bob Wright<[log in to unmask]>
Mark Rode<[log in to unmask]>
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